Preparation method of ultrahigh molecular weight polyethylene fiber

[0012] See figure 1 with figure 2 The main difference between the method of the present invention and the method of the prior art is that the present invention performs a primary drafting and a secondary drafting in sequence before extraction. Among them, the multiple of the primary drafting can be 2 to 8 times, and the multiple of the secondary drafting can be 1.1 to 3 times, and the thermal drawing multiple of the present invention is lower than the prior art, and the range is 30 to 45. Therefore, the fiber obtained in the present invention has a lower fineness while still maintaining a higher breaking strength. The present invention will be further described in detail below in conjunction with specific embodiments.

[0013] A preparation method of ultra-high molecular weight polyethylene fiber includes the following steps:

[0014] (1). Preparation of frozen collagen filaments of ultra-high molecular weight polyethylene: UHMWPE (viscosity average molecular weight 4.5 million), solvent white oil 70 # , Respectively inject into the unwrapping kettle according to the mass ratio of 8:100, shear for 25 minutes under the protection of nitrogen, and the shear rate is 3000 seconds -1 , The emulsion mixture is obtained, and then the mixture is fed into the twin-screw extruder, the diameter of the screw extruder is 95mm, the ratio of length to diameter is 64, the rotation speed is 160rpm, and the extrudates output by the screw extruder are successively After passing through the filter, box and metering pump, it is sprayed from the spinneret hole (diameter 0.7mm, hole number 100~200f) of the spinneret, and then enters the water bath containing 1wt% surfactant at 15℃~40℃ to solidify. The frozen collagen filament;

[0015] (2) Pre-drawing the frozen collagen filament obtained in step (1), specifically, first-stage drafting with a multiple of 3 to 8 times, and then a second-stage drafting with a multiple of 1.1-2.5 times.

[0016] (3) Use the hydrocarbon cleaning agent as the extractant to extract the frozen collagen filaments that have passed through step (2), then dry, and heat-stretch 35 times to obtain a total denier of 50 to 200D, and a single filament size of 1 to 2D ultra-high molecular weight polyethylene fiber. After testing, the fiber breaking strength is more than 40cn/dtex, the modulus is more than 1200g/d, and the fiber denier unevenness is less than 6%.

[0017] The present invention has been described in detail above, and its purpose is to enable those skilled in the art to understand the content of the present invention and implement it, but it cannot limit the scope of protection of the present invention. Anything done in accordance with the spirit of the present invention, etc. The effect changes or modifications should be covered by the protection scope of the present invention.